Gingipains in the culture supernatant of Porphyromonas gingivalis cleave CD4 and CD8 on human T cells

Porphyromonas gingivalis has been shown to attack host defense systems through proteolytic cleavage of a wide variety of members of the systems. In this study, we examined the ability of P. gingivalis culture supernatant to alter the expression of human T cell surface proteins. As judged by flow cytometric analysis, detection of CD4 expression was completely eliminated by the supernatant, but CD8 was less sensitive. When the culture supernatant was added with reducing agents, proteolytic activity was enhanced, resulting in the cleavage of CD8. Mitogenic response of T cells to phytohemagglutinin or concanavalin A was decreased by the treatment of the cells with the culture supernatant of P. gingivalis. The three forms of gingipains (high molecular mass arginine-specific gingipain, arginine-specific gingipain 2 and lysine-specific gingipain) purified from the culture supernatant of P. gingivalis actively cleaved CD4 and CD8 on human T cells, indicating that proteolytic activity of the culture supernatant was due to gingipains. These results suggest that cysteine proteinases like gingipains released from P. gingivalis cleave T cell surface proteins and impede T cell function.     

Survey of congenital anomalies associated with cleft lip and/or palate in 701,181 Japanese people

There have been many reports on congenital anomalies associated with cleft lip and/or palate (CL/CLP) in Japan. However, these reports included data only on patients who came to hospitals; thus the real situation regarding these anomalies remains unclear. Therefore, we surveyed newborns at all delivery facilities in the central area of Japan for the presence of these anomalies, following their progress for 12 consecutive years; at the end of that time, questionnaires were collected and analyzed. In this article, we describe our results.     

A multifocal neurinoma of the hypoglossal nerve with motor paralysis confirmed by electromyography

A rare case of neurinoma in a 72 year-old Japanese woman derived from the hypoglossal nerve is reported. The tumour was composed of three interconnected nodules occurring simultaneously in the left submandibular and sublingual regions. The lesion, which presented as a neck mass, caused a slight left-sided hemiparesis of the tongue with tongue deviation to the affected side not noticed by the patient. An electromyographic (EMG) study revealed decreased muscle activity on the left side of the tongue muscle, indicating dysfunction of the hypoglossal nerve. EMG was useful for diagnosis.     

A lip seal study of Japanese children with malocclusion

The purpose of this study was to clarify the relationship between lip seal and malocclusion in Japanese children. Fifty-three patients aged 7 to 14 years (mean 10.24 +/- 1.93) were selected randomly, and compared with 20 subjects with normal occlusion aged 7 to 14 years (mean 10.50 +/- 2.56). The subjects were divided into a good lip seal group and poor lip seal group by observing the distance between the upper and lower lip at rest. The variables that were analyzed for morphological evaluation included model analysis and cephalometric analysis. Noted for functional evaluation were tongue position, the size of the tonsils and adenoids and the oral muscle force measured by button pulling. In the evaluation of the degree of lip seal, there was no statistical difference between subjects with malocclusion and those with normal occlusion. Within the group with malocclusions, however, there were significant differences in overbite (p < 0.01), overjet (p < 0.01), and oral muscle force by button pulling (p < 0.05) between the good lip seal and poor lip seal groups. These results suggest that there is a need not only to correct malocclusion but also to be aware of lip sealing so that it may be improved in Japanese children.     

The involvement of bradykinin in adrenaline-induced pulmonary edema in rats

We investigated the effect of endogenous bradykinin on adrenaline-induced pulmonary edema (PE) by blocking bradykinin receptors. In preliminary experiments, a bolus injection of adrenaline (ADR; 10 microg/kg) solution (10 microg/ml) was determined to be an edematogenic dose for inducing PE. The lung body weight index (LBI) and incidence of PE (IPE) were determined. The IPE and LBI of the group pretreated with Des-Arg9-[Leu8]-Bradykinin (DA-BK, 50 microg/kg, 50 microg/ml) increased significantly compared with those of the control group (p<0.05). On the other hand, there were no remarkable changes in IPE and LBI in the groups pretreated with Hoe140 (D-Arginyl-[Hyp3, Thi5, D-Tic7, Oic8]-Bradykinin (100 microg/kg, 100 microg/ml), captopril (20 mg/kg, 20 mg/ml) or L-NAME (1 mg/kg, 1 mg/ml). Moreover, the IPE and LBI of the group co-treated with L-NAME and DA-BK decreased compared with the DA-BK group (p<0.05). Thus, bradykinin aggravates adrenaline-induced PE through activation of the B2 receptor by the kallikreins as a result of the ADR administration, although the precise mechanism is not known.     

Comparison of four methods of assessing root surface debridement

BACKGROUND: While there is great interest in measuring the efficacy of root surface debridement, there is little consensus on how this might be best achieved. The aim of this study was therefore to compare four different methods of assessing root surface debridement in their ability to discriminate between ultrasonically instrumented root surfaces and non-instrumented control surfaces. METHODS: Single-session subgingival root debridement was performed by an experienced operator on 30 teeth prior to their extraction. Following extraction, efficacy of root surface debridement was measured by percentage of remaining calculus, instrument efficiency, modified instrument efficiency, and percentage apical plaque border. In addition, the effect of probing depth landmark (apical plaque border versus connective tissue attachment) on outcomes was assessed. RESULTS: The results indicated that percentage apical plaque border demonstrated highly statistically significant differences between instrumented and control surfaces (P= 0.02). No other assessment method was able to discriminate between instrumented and non-instrumented surfaces, and this may be a function of the low amount of root surface calculus in the experimental sample. In addition, choice of probing depth landmark had a notable effect on the outcomes for instrument efficiency and modified instrument efficiency. Ninety-five percent limits of agreement of interexaminer reproducibility were found to be much higher than intra-examiner measurement for all four methods of assessment. CONCLUSIONS: Percentage apical plaque border appeared to be potentially more useful than other methods for assessing the efficacy of debridement of periodontally involved root surfaces, particularly for measuring instrument penetrability.     

Cloning, characterization and immunolocalization of human ameloblastin

Amelogenesis imperfecta is a broad classification of hereditary enamel defects, exhibiting both genetic and clinical diversity. Most amelogenesis imperfecta cases are autosomal dominant disorders, yet only the local hypoplastic form has been mapped to human chromosome 4q between D4S242 1 and the albumin gene. An enamel protein cDNA, termed ameloblastin (also known as amelin and sheathlin), has been isolated from rat, mouse and pig. Its human homolog has been mapped to chromosome 4q21 between markers D4S409 and D4S400, flanking the local hypoplastic amelogenesis imperfecta critical region. Therefore, ameloblastin is a strong candidate gene for this form of amelogenesis imperfecta. To facilitate genetic studies related to this dental disease, we isolated and characterized a human ameloblastin cDNA. A human third molar cDNA library was screened and two ameloblastin clones identified. Nucleotide sequencing of these cDNAs indicated alternative splicing of the putative open reading frame, use of different polyadenylation signals, and a high degree of similarity to reported rat, mouse and porcine cDNAs. Immunohistochemistry studies on embryonic human teeth using an antibody to recombinant ameloblastin indicated ameloblastin expression by ameloblasts with localization in the enamel matrix associated with the sheath structures.     

Differential diagnosis of calcium pyrophosphate dihydrate deposition of the temporomandibular joint

Calcium pyrophosphate dihydrate (CPPD) deposition disease (pseudogout) of the temporomandibular joint (TMJ) is rare. It is characterized by the presence of crystal deposits that are birefringent under polarized light. Although these crystals are characteristically weakly birefringent, some other crystals such as those of calcium oxalate, synthetic steroids, and ethylenediaminetetraacetic acid are also birefringent. The differential diagnosis should therefore be based on a quantitative analysis of crystals or observation of the crystal structure in calcified sections. We present a case of CPPD deposition disease of the TMJ and report on the value of such an analysis to substantiate the diagnosis.     

Bacteriologic features and antimicrobial susceptibility in isolates from orofacial odontogenic infections

OBJECTIVE: The aim of this study was to obtain information for an effective antimicrobial therapy against orofacial odontogenic infections; such information was obtained from recent bacteriologic features and antimicrobial susceptibility data. STUDY DESIGN: The bacteriology and antimicrobial susceptibility of major pathogens in 163 patients with orofacial odontogenic infections to 7 antibiotics was examined. RESULTS: Mixed infection of strict anaerobes with facultative anaerobes (especially viridans streptococci) was observed most often in dentoalveolar infections, periodontitis, and pericoronitis. Penicillin (penicillin G) was effective against almost all pathogens, although it did not work well against beta-lactamase-positive Prevotella. Cefmetazole was effective against all test pathogens. Erythromycin was ineffective against viridans streptococci and most Fusobacterium. Clindamycin exerted a strong antimicrobial activity on anaerobes. Minocycline was effective against almost all the test pathogens. The antimicrobial activity of levofloxacin against viridans streptococci was not strong. CONCLUSIONS: An antibiotic that carries out antimicrobial activity against both viridans streptococci and oral anaerobes should be suitable for treatment of dentoalveolar infection, periodontitis, and pericoronitis. Penicillin remains effective as an antimicrobial against most major pathogens in orofacial odontogenic infections. Cefmetazole, clindamycin, and minocycline may be effective against most pathogens, including penicillin-unsusceptible bacteria.     

Odontogenic ghost cell carcinoma: a case report with reference to the relation between apoptosis and ghost cells

The neoplastic variant of calcifying odontogenic cyst has various designations, and its malignant counterpart has been reported as aggressive epithelial odontogenic ghost cell tumor or odontogenic ghost cell carcinoma. We present a case of odontogenic ghost cell carcinoma with reference to the relation between the ghost cells and apoptosis. A 33-year-old man complained of a mandibular mass. The mass occupied the entire right side of the mandible with destruction of both buccal and lingual bone. The mass also infiltrated into submandibular and sublingual spaces. Histologically, the mass was composed of a solid proliferation of hyperchromatic and pleomorphic epithelial cells with abnormal mitoses. Islands of ghost cells were frequently admixed with nucleated cells, and there were foci of ameloblastic differentiation. Immunohistochemical stains for cytokeratins, involucrin, and apoptosis-related proteins such as Bcl-2, Bcl-X(L), and Bax were done. Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL) assay was also performed. The nucleated cells adjacent to the ghost cells expressed cytokeratins and involucrin, but the ghost cells had no reaction. Bcl-2 was negative. Both Bcl-X(L) and Bax were demonstrated in the nucleated cells adjacent to the ghost cells. The ghost cells exhibited Bax protein. Some nucleated cells adjacent to the ghost cells were positive with TUNEL assay. The above results indicate that ghost cells undergo abnormal terminal differentiation as an apoptotic process.